Decription:
Sometimes you cannot get to the right focal plane for focusing with a camera or eyepiece. You can use this extender with any camera or eyepiece or with various adapters. The M54*0.75 threads on both ends make it extremely versatile. Use this extender for obtaining the correct image scale or for the exact spacing required for a reducer or field flattener. You can reach the extension length required by combining several extenders of different lengths.
Parameter:
1.M54*0.75 extension cylinder rear intercept adjustment ring 4-20MM optional
2.The Extension Ring has length of 4mm,5mm,6mm,7mm,8mm,9mm,10mm,15mm,20mm.
3.Scope of application: back intercept of photography
4.Outer diameter: 60mm.
5.Black matte black finish.
6.Pitch: 0.75.
7.Male thread length: 3mm.
8.Length of internal thread is as follows:
4mm-female thread length is 3mm.
5mm-female thread length is 4mm.
6mm-female thread length is 4.5mm.
7mm-female thread length is 5.5mm.
8mm-female thread length is 6mm.
9mm-female thread length is 7mm.
10mm-female thread length is 8mm.
20mm-female thread length is 8mm.
Package Includes:
1x M54*0.75 Extension Tube.

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Origin : Mainland China
Name : M54x0.75 Rear intercept Extended Focal Ring
The length of Extension Ring : 4mm,5mm,6mm,7mm,8mm,9mm,10mm,15mm,20mm.
Scope of application : back intercept of photography
Outer diameter : 60mm.
Feature : Black matte black finish.
Pitch : 0.75.